The vial with lyophilizate contains 1.77 mg of sodium / vial (0.354 mg / ml), which should be taken into account in patients who are on a hyponatrial diet.
The use of the drug may cause hypersensitivity reactions, including anaphylaxis. In case of their occurrence, it is necessary to have the necessary drugs and equipment for immediate medical care.
The preparation should be prepared and applied only by qualified personnel in the department of nuclear medicine in conditions asepsis. The introduction of radiopharmaceuticals creates risks of external radiation contamination with urine, vomit, etc.Precautions should be observed when working with radioactive materials, as well as the conditions for aseptic work with the drug. The finished product is stored in accordance with national rules for ensuring radiation safety. Any unused radioactive material is disposed of in accordance with applicable law.
Before using the drug, to confirm the quality, it is necessary to determine the radiochemical purity of the drug according to the following procedure:
Determination of radiochemical purity
In the prepared solution of exometasim for injection, three potential impurities may be present. This is a secondary complex 99mTc-eksametazima, free pertechnetate and reduced-hydrolyzed 99mTc. To fully determine the radiochemical purity of the drug solution, two chromatographic systems should be used: butane-2-one (MEK) and 0.9% sodium chloride solution.
The samples of the test solution are applied with a needle about 2.5 cm from the lower edge of the two chromatographic strips Varian SA (2 cm (± 2 mm) x 20 cm). After that, the strips are immediately placed in the prepared chromatographic chambers, which contain a fresh solvent with a layer thickness of 1 cm, for ascending chromatography.After moving solvent front to 14 cm from the start, the strip is removed from the chromatographic chamber, dried and radioactivity was determined using suitable equipment.
Chromatography results System 1 (Varian SA: Butan-2-one (MEK)
Secondary complex 99mTc-eksametazima and reduced-hydrolyzed 99mTc remain on the sample line.
Lipophilic complex 99mTc-eksametazima and pertechnetate move with the front (Rf 0,8-1,0).
System 2 (Varian SA: 0.9% sodium chloride)
Lipophilic complex 99mTc -exexametasim, secondary complex 99mTc-eksemetazim and
reconstituted-hydrolyzed 99mTc remain at the start.
Pertechnetat moves with Rf 0,8-1,0.
Calculate the activity (%) due to the complex 99mTc -exexamazime and reduced-hydrolyzed 99mTc on the chromatograms of System 1 (A%). Calculate the activity (%) due to pertechnetate according to System 2 chromatograms (B%). Radiochemical purity (as a percentage of the lipophilic complex 99m-eksametazima are defined as follows: 100 - (% A +% B), where A% - level secondary complex 99mTc -exexametam and reconstituted-hydrolyzed 99mTc; In% - the level of pertechnetate.
When sampling for the test within 30 minutes after preparation of the drug solution, it can be expected that the radiochemical purity will be at least 80%. The test for determination of radiochemical purity should be carried out immediately after sampling.
The procedure for the isolation of leukocytes and their subsequent labeling in vitro 99mTc-exometasim
All operations should be performed in compliance with aseptic methods.
1. In two 60 ml plastic non-heparinized syringe, dial 9 ml of a mixture consisting of a solution of citric acid - dextrose citrate (see "Notes").
2. In each of the syringes, using a butterfly needle (19G), select 51 ml of blood from the patient. Close the syringes with sterile tips.
3. Prepare 5 universal tubes and add 2 ml of hydroxyethyl starch solution.
4. Without inserting the needle into the syringe, transfer 20 ml of blood from the syringes to each of the 5 universal tubes containing hydroxyethyl starch. The remaining 20 ml of blood is transferred to a tube that does not contain hydroxyethyl starch.
Recommendation: to prevent the formation of bubbles and foaming, the blood should be carefully drained over the walls of the test tubes.
5. Gently mix blood and hydroxyethyl starch by a single overturning of the test tube. Remove the cap from the universal tube and remove any air bubbles with a sterile needle. Put on the lid and allow the tubes to settle for 30-60 minutes to settle the red blood cells.
Recommendation: the rate of erythrocyte sedimentation depends on the patient's state of health. The process can be considered complete when the red blood cells settle at least half of the entire volume of the tube.
6. In parallel, a second tube, free from hydroxyethyl starch and containing 20 ml of whole blood, is centrifuged at 2000 g within 10 minutes. The resulting supernatant contains a cell-free plasma and a citric acid solution, dextrose citrate, and stored at room temperature. The supernatant is used as an environment for labeling leukocytes.
7. After the completion of the process of precipitation of erythrocytes in the first tube, carefully, avoiding the entry of red blood cells, transfer 15 ml of supernatant (turbid liquid of pale yellow color), consisting of plasma with leukocytes and platelets, into pure universal test tubes.
Recommendation: When sampling, do not use the needle to avoid accidental cell damage.
8. The resulting supernatant is centrifuged at 150 g for 5 minutes to obtain a supernatant consisting of plasma with platelets, and a sediment - a "mixture" of leukocytes.
9. The maximum possible amount of supernatant is transferred to clean universal tubes and centrifuged at 2000g for 10 minutes to obtain an additional supernatant fluid free of plasma cells. The resulting supernatant contains hydroxyethyl starch and will be used to wash the cells after inserting a label in them.
10. In parallel, gently tapping and rotating the tube, detach from the walls sediment, which is a "mixture" of leukocytes. A syringe without a needle, put the cells in one tube and, using the same syringe, add 1 ml of the supernatant obtained in step 6. Gently rotating the tube, resuspend the cells.
11. Using the procedure described in the paragraph "Preparing the preparation," prepare a solution 99mTc-eksametazima, by adding from the generator 99mTc 5 ml eluate with content 99mTc O4-500 MBq (13.5 mCi).
12. Immediately add 4 ml of the prepared solution 99mTc-eksametazima in the "mixture" of leukocytes and supernatant (see item 10).
13. Caution Rotate the tube, mix the contents and leave for 10 minutes at room temperature.
14. If necessary, immediately apply the samples to chromatographic strips for the assessment of radiochemical purity 99mTc-exometasim according to the instructions set forth in the paragraph "Determination of radiochemical purity".
15. In order to stop the process of introducing labels into the cells, after 10 minutes in a test tube Caution add 10 ml of supernatant (see point 9), cell-free and containing hydroxyethyl starch. Mix the contents of the tube with a gentle rotational motion.
16. Centrifuge at 150 g within 5 minutes.
17. Select and store the supernatant.
Recommendation. It is necessary that at this stage the entire supernatant containing unbound 99mTc-eksametazim, was maximally completely taken from the tube, for which a needle with a wide channel is used.
18. Rotating gently for mixing, resuspend the leukocyte mixture, QQ labeled 99mTc, in 5-10 ml of the supernatant obtained in step 6.
19. Measure the radioactivity of cells and supernatant from point 17.Calculate the efficiency of the labeling process in percent, which is defined as the ratio of activity in cells to the sum of activities in cells and supernatant.
Recommendations. The effectiveness of the labeling process depends on the number of leukocytes in the patient and varies depending on the volume of the sample of the selected blood. When using the volumes specified in clause 2, the expected effectiveness of the labeling process [LE] will be about 55%.
20. With a syringe without a needle, gently take the labeled cells into a plastic, non-heparinized syringe and close it with a sterile cap. Measure radioactivity.
21. After this, the labeled cells are ready for administration, which should be carried out without delay.
Notes: To prepare 1 liter of a mixture of a solution of citric acid - dextrose citrate, you should transfer 22 g of trisodium citrate, 8 g of citric acid, 22.4 g of dextrose to a graduated flask and bring the volume of water for injection to 1.0 liters. All operations should be performed in compliance with aseptic methods. Sterilize by filtration through a Millipore filter (0.2 μm). Store at room temperature.It is allowed to use a ready-made industrial solution, which must be stored in accordance with the manufacturer's recommended conditions and used before the expiration date.
Preparation of 6% hydroxyethyl starch should also be carried out in accordance with aseptic methods. It is allowed to use a ready-made industrial solution, which must be stored in accordance with the manufacturer's recommended conditions and used before the expiration date.
It is important that the labeled leukocytes are thoroughly washed before being administered to the patient.